Xgen import as reference

[Anonymous]

Hi everyone.

I meet a problem about Xgen, with you can help me to fix the problem. 

Thank you

I have three characters with hair created by Xgen system. In the original file, the hair can move correctly, both dynamic curve(create by nhair) and hairs(create by Xgen) generate from the surface.  please see image correct 1,2,3

However, once I import all the three characters as reference or import directly in the my main scene file,  the hair will sink into the surface while I press play button. (the dynamic curve appear correctly)

please see image incorrect 1,2.

[Michael_Todd · Accepted solution]

How are the curves being driven in the scene after referencing? Are you using a cache (alembic) to drive the guides or via an aimwire/linearwire modifier? or are you just using a hair system cache?

[Anonymous]

Thank you replying me 

I do not know which curve you questioned. 

The way I create the hair is that I create the hair style by Xgen first

then, using create hair system to create nhairsystem and curves. Then sellect those curve created automatically by hair system to attach hair system.

afterward，I import the file to my mainscene as reference.

I do not use any cache at the moment because I do not do animation.

It is my original file' outliner.

I use those curves under the group(GirlhairSystem1OutputCurves) to attach hair system.

Thank you 

[Anonymous]

you can see that the curves move same in the two scenes.But the hairs fall into the geometry.

[Michael_Todd]

and if you turn off 'Use Animation'? What does the hair do then?

 also, do you have multiple hairs systems referenced in the final scene? have you tried creating a cache of the hairsytem output curves and using that instead of a live connection to an nHair system?

I just tried referencing an XGen groom where it uses an nHairsystem to drive guides and it worked fine. Did you select the output curves and attaching them after referencing the scene?

Cheers

[Anonymous]

if you turn off 'Use Animation', the hair will show correctly. 

But they cannot move.

[Anonymous]

Once I turn on the 'use animation' and press play button, the hair will fall into the surface.

[Michael_Todd]

I notice that in your screen grabs, you are grouping the XGen collection with the geo, nHair system and output curves. This is not a recommended practice. I'd suggest taking the XGen collection out of the group and keeping it separate to avoid double transforms. 

You might want to regenerate the nHair cache in the final scene as well, if the hairsystem in the final scene is not in the same space as the original scene, you might get an offset.

[Anonymous]

Yea I have three hairs system referenced in the final scene. If I create a Alembic cache from the original scene and use the cache file in the final scene instead of a live connection to an nhair system, they will be like that. image 1.

and if I create a Alembic cache in final scene, they will fall in again.

And I make sure I have attached the output curves to Hair system after referencing the scene.

this is my Character's hierarchy.I use the 'girl_master_CTL' to move the character, I donot move the hairsystem. image2

If divide them to two group like this  image 3 

My final scene will get a colletion more without description. Furthermore, the hair will fall into body again. image 4

If I separate thoroughly the hairsystem from the group.like this image 5

there will two collection again, one the them without description. and there are two hairsystem in outliner. furthermore, my character cannot show the hair anymore. like image6

Furthermore, I move the character in the original file, the hair show correctly, so, I guess it not created by transforms.

Thank you for your patient. 

[Michael_Todd]

For this type of scene. I think you need to use a different workflow, where you export the XGen collection and import it directly into the scene with the character in the final reference scene.

In your groom scene, export the xgen collection to disc. 

this will save out the XGen file to the location you specify. Delete the collection from the character scene but make sure the geo that XGen was bound to (the scalp for the head, say) is still in the scene. Just make sure there is no XGen collection in the scene and save it, making a character only scene for referencing. Effectively you are publishing a groom file and a character scene separately.

In the final scene, reference in the Character scene first. This will put the character in a namespace. Import, via the XGen UI, the Xgen file you exported earlier, making sure to import it into the same namespace as the character. 

The collection will be imported and so long as the geo that this collection was bound to in the groom scene is still present, the bindings will be recreated and the groom will be rebuilt on the relevant geo.

Then you can re-attach the output curves to the  descriptions. if you set the XGen log to 2 or higher for warnings and stats, it will give you info on any problems encountered.

When you created the cache for use instead of suing live mode, did you seekct the group or the actual curves?

Cheers

Michael

[Anonymous]

I export the geometry and the collection separately. then I import the collection and geometry in my main scene. the hair still sink into body.

[Michael_Todd]

there must be an offset being introduced somewhere between the groom scene and the scene referencing it. I can create a groom scene with nHair driving the guides and reference it without issue, even when using the same kind of grouping that is not really recommended.

Groom Scene:

groom Scene referenced:

Is there any scaling being introduced anywhere? Are you using worldspace when exporting the alembic cache?

With out the scene to hand it's hard to pin down the cause as the workflow you are using does work, but for some reason, an offset seems to be being introduced somewhere...

Cheers

[Anonymous]

Thank you very much! I gonna check my scene again. !

[Anonymous]

Hi Micheal

Finally, my teacher found  the problem.

If I turn off the 'Trapped Check' under the nrigid. image1

But I don't know the reason.

Thank you very much!